In the six months since he was fired by Fox News over the revelation of multiple settlements paid to women who had accused him of sexual harassment andof inappropriate behavior, O'Reilly has become decidedly less visible. After reaching millions of people each night on "The O'Reilly Factor," long the number one show on cable news, O'Reilly now commands a significantly smaller audience online.

But it is a testament to the O'Reilly brand that "Killing England," his latest book and the first to hit shelves since his ouster at Fox, has still been a commercial success. It's claimed the top spot on the hardcover nonfiction category of the New York Times' best seller list for the last three weeks, even besting "What Happened," the highly-anticipated new memoir from Hillary Clinton.

But its sales have been dwarfed by previous installments in O'Reilly's wildly successful "Killing" series, a collection of pop history books he's co-authored with Martin Dugard. "Killing England" sold 212,000 copies in the four weeks since its September 19th release, according to The NPD Group, a marketing research company that measures book sales. It's thelowest opening month of sales since the first title in the series, 2011's "Killing Lincoln," which sold 190,000 in the first four weeks.

The previous five "Killing" books each outsold "Killing England" in their first month on shelves by more than 100,000 copies. Two books, "Killing Patton" and "Killing Jesus," each eclipsed 400,000 copies in the four weeks following their release.

But O'Reilly's future as an author was thrust into uncertainty on Thursday, when William Morris Endeavor, which handles his book deals, said it will drop him as a client after his contract expires. Before that, O'Reilly was dropped by United Talent Agency, where his television agent there represented him for decades.

The abrupt cancellation of the "O'Reilly Factor," which drew nearly four million people on some evenings, denied O'Reilly a precious promotional vehicle. Night after night, O'Reilly hawked his myriad bestsellers, urging viewers to become premium members of his official website in exchange for a copy of one of the books. O'Reilly was able to use Fox to promote "Killing England," going on Sean Hannity's talk show last month for what was a highly-rated episode.

The Washington Post reported previously that O'Reilly's book sales dipped precipitously after he was sacked by Fox in April. And O'Reilly's chances of staging a TV comeback may have been severely damaged last weekend, when the New York Times reported on a $32 million settlement paid to a former Fox News personality who accused O'Reilly of sexual misconduct.

O'Reilly decried the latest revelation as a smear and accused the Times, which also reported on the settlements that led to his firing in the spring, of trying to take him out of the marketplace. Earlier this week on his podcast, "No Spin News," O'Reilly claimed that the Times was motivated by the success of his new book and fledgling online enterprise.

"And so the New York Times said, 'You know, we didn't kill him, so we've got to kill him again,'" O'Reilly said. "So they came back with another bunch of garbage."

"No Spin News," which is posted four nights a week on O'Reilly's website and can be accessed only by a paid membership, has become his primary post-Fox platform. O'Reilly has repeatedly touted the success of the show, which is sometimes recorded in studio space owned by Newsmax, a conservative outlet that has been floated as a possible landing spot.

In June, O'Reilly told Newsmax that the show draws "hundreds of thousands" of people. He said this week that his website had more than 300,000 visitors on Monday night, when he used "No Spin News" to deliver a dramatic rebuttal to the allegations.

But the site traffic has dried up in the months since he was dropped by Fox. According to comScore, a data analytics company, BillOReilly.com drew 469,000 visitors in April, the month of his firing. But O'Reilly was unable to sustain that audience throughout the summer and, last month, the site had only 125,000 visitors, its lowest total in two years.

The site now serves as O'Reilly's primary promotional vehicle and, just as he did for years on the "Factor," he dutifully promotes his merchandise to people who are still buying what he's selling.

On Wednesday's edition of his show, O'Reilly read a message from one such fan.

"Bill, any time the media puts out fake stories about you," the fan wrote. "I purchase something on BillOReilly.com."

CNNMoney (New York) First published October 26, 2017: 12:56 PM ET

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